Most recent issue published online for the International Journal of Environmental Engineering.

Application of biofilm membrane bioreactor and Reverse Osmosis membrane to the treatment of fresh and partially stabilised leachate

Chart Chiemchaisri — 2011-07-20T23:20:50-05:00

Application of biofilm membrane bioreactor and Reverse Osmosis membrane to the treatment of fresh and partially stabilised leachate
Chart Chiemchaisri, Sujirut Putthiwara, Adisorn Chanpeng
International Journal of Environmental Engineering, Vol. 3, No. 3/4 (2011) pp. 210 - 220
Membrane Bioreactor (MBR) with sponge cube media and reverse osmosis (RO) were investigated in laboratory scale. Fresh and partially stabilised leachate contained COD/N of 30 and 10 and BOD/COD of 0.7-0.9 and 0.4-0.7, respectively. Continuous and intermittent aeration modes were examined. COD and TKN removals were more than 90%. Highest nitrogen removal efficiency was achieved when aeration of 1 h on and 2 h off cycle were employed. The effluent from MBR was further treated in RO unit with average rejection efficiencies of 75% 97%, 94% and 99% for COD, NH4+, SO42− and PO43−, respectively.

Kinetic study of toxic pollutants decomposition by ozone in landfill leachate using a numerical adaptive method

Tatyana Poznyak — 2011-07-20T23:20:50-05:00

Kinetic study of toxic pollutants decomposition by ozone in landfill leachate using a numerical adaptive method
Tatyana Poznyak, Isaac Chairez
International Journal of Environmental Engineering, Vol. 3, No. 3/4 (2011) pp. 221 - 239
This study describes a new method to perform the kinetic study of toxic pollutants decomposition by ozone in landfill leachate using a novel numerical adaptive method based on the classical least square method. The leachate was obtained from the Mexico City waste sanitary landfill (Bordo Poniente) and was treated by ozonation after a coagulation treatment with Fe2(SO4)3. For the partial identification of the initial organic matter composition, intermediates and final products of ozonation, the extraction of the initial and ozonated leachate with benzene, chloroform : methanol (2 : 1) and hexane was carried out, and then the extracts were analysed with a gas chromatography.

A laboratory-scale mixed multibarrier for removal of ammonium from landfill leachate contamination

Thomas Van Nooten — 2011-07-20T23:20:50-05:00

A laboratory-scale mixed multibarrier for removal of ammonium from landfill leachate contamination
Thomas Van Nooten, Ludo Diels, Leen Bastiaens
International Journal of Environmental Engineering, Vol. 3, No. 3/4 (2011) pp. 240 - 252
A column-scale multibarrier, combining nitrification and ion exchange processes in a mixed configuration, was evaluated for the removal of ammonium (325 ± 60 mg N L−1) from landfill leachate contamination. Inoculating granular clinoptilolite with nitrifying bacteria resulted in a 3.2 times higher overall ammonium removal, compared with a non-inoculated control. Interestingly, nitrifying activity resulted in desorption of ammonium from saturated clinoptilolite and subsequent microbial oxidation of the released ammonium. These findings indicate that ammonium-saturated clinoptilolite can be in-situ bioregenerated in a multibarrier, which implicates that periodic (and particularly costly) removal and external regeneration of the ion exchange material can be avoided.

Persistent Organic Pollutants (POPs) in leachates from municipal landfills

Marzenna R. Dudzinska — 2011-07-20T23:20:50-05:00

Persistent Organic Pollutants (POPs) in leachates from municipal landfills
Marzenna R. Dudzinska, Jacek Czerwinski
International Journal of Environmental Engineering, Vol. 3, No. 3/4 (2011) pp. 253 - 268
The leachates from six municipal waste landfills, located in South-eastern Poland, were studied for the presence of major, Persistent Organic Pollutants (POPs) – PAHs, Polychlorinated Dibenzo-p-dioxins (PCDDs)/Polychlorinated Dibenzofurans (PCDFs), Polychlorinated Dibenzothiophenes (PCDTs) and Polybrominated diphenyl ethers (PBDEs). The measured concentrations varied with respect to the particular compound and landfill, but POPs were present at measurable levels in the leachates from all the examined landfills. The highest concentrations were found in the leachate from the landfill collecting waste from the capital of the province. In the leachates from younger landfills, the concentrations of lower halogenated compounds were higher than those of higher substituted congeners. Lower condensed PAHs showed higher concentrations in samples from all the examined sites.

In-situ moisture content measurement of landfill cover using Time Domain Reflectometry

Dawit Tecle — 2011-07-20T23:20:50-05:00

In-situ moisture content measurement of landfill cover using Time Domain Reflectometry
Dawit Tecle, Jejung Lee
International Journal of Environmental Engineering, Vol. 3, No. 3/4 (2011) pp. 269 - 283
The amount of methane that vent from landfills is dependent on the physical, chemical and biological components of the soil cover; moisture content and temperature of the soil being the major controlling factors. Previous studies have attempted to correlate moisture content and temperature with methane emission by collecting soil samples from landfill soil covers and analysing it in the laboratory for moisture content determination. Moisture content, temperature and methane data of the landfill soil cover were collected and analysed. Methane emission showed good temporal correlation with soil temperature, however no significant relationship between moisture content and methane emission was observed.

Mitigating methane emissions from passive landfill vents: a viable option for older closed landfills

Tarek Abichou — 2011-07-20T23:20:50-05:00

Mitigating methane emissions from passive landfill vents: a viable option for older closed landfills
Tarek Abichou, Lei Yuan, Jeffery Chanton, Jose Morales
International Journal of Environmental Engineering, Vol. 3, No. 3/4 (2011) pp. 284 - 297
This study investigated the use of biofilters to reduce methane emissions from landfill passive gas vents. Two biofilter designs were evaluated. The two filter designs achieved similar percent oxidation averages. The radial biofilter design, however, obtained a much higher methane oxidation rate. The higher surface area of flow in the radial biofilters decreased the methane influx leading to greater oxygen penetration into the biofilters. An average percent oxidation of 20% and higher were obtained when air temperature was 20-36°C, indicating the optimal soil temperature for methanotrophs to oxidise methane.

Evaluation of methane oxidation in a landfill cover material using a simple indicator approach

Jonathan A. Lafond — 2011-07-20T23:20:50-05:00

Evaluation of methane oxidation in a landfill cover material using a simple indicator approach
Jonathan A. Lafond, Suzanne E. Allaire, Alexandre R. Cabral
International Journal of Environmental Engineering, Vol. 3, No. 3/4 (2011) pp. 298 - 317
Estimates of methane (CH4) oxidation rates (Rg) in biocovers are crucial for development of abatement strategies. Rg values were estimated in a landfill biocover with a simple approach based on gas diffusion theory. Rg varied from 0 to 1.1 × 10−6 kg m−3 s−1. Highest oxidation efficiencies reached 80-100% when soil water content < 40%, temperature > 20°C and O2 concentration > 0.1 kg m−3. Rg was correlated to oxidation efficiency measured by stable isotopes and surface emissions. The approach allows for affordable continuous monitoring of Rg, but only gives a rough estimate of CH4 oxidation rate.

Alternative stabilisation options of mechanically sorted organic fraction from municipal solid waste prior to landfill disposal

Vincenzo Belgiorno — 2011-07-20T23:20:50-05:00

Alternative stabilisation options of mechanically sorted organic fraction from municipal solid waste prior to landfill disposal
Vincenzo Belgiorno, Daniele Panza, Lara Russo, Valeria Amodio, Alessandra Cesaro
International Journal of Environmental Engineering, Vol. 3, No. 3/4 (2011) pp. 318 - 335
In order to foresee the measures of the Directive 1999/31/EC, waste management policies are focused on the reduction of organic matter landfill disposal, through the recovering of the organic waste stream or the pre-treatment of residual wastes before landfilling. This paper discusses the advantages and disadvantages of possible stabilisation treatments of the mechanically sorted organic fraction of municipal solid waste, to identify the most suitable management action, with regard to landfilling impacts. Experimental results demonstrate that chemical treatment of organic residue provides only temporary stabilisation, while anaerobic digestion treatment represent an interesting option thanks to its energetic and environmental benefits.

Evaluation of a sequential aerobic anaerobic treatment of municipal solid waste in a bioreactor landfill

Aris Nikolaou — 2011-07-20T23:20:50-05:00

Evaluation of a sequential aerobic anaerobic treatment of municipal solid waste in a bioreactor landfill
Aris Nikolaou, Apostolos Giannis, Evangelos Gidarakos
International Journal of Environmental Engineering, Vol. 3, No. 3/4 (2011) pp. 336 - 348
A sequential aerobic-anaerobic bioreactor landfill was operated and monitored over a period of 184 days. The bioreactor was filled with 120 kg of organic fraction of Municipal Solid Waste. Leachate recirculation was applied. The results showed rapid degradation of organic matter with rapid settlement during the aerobic period. The initial COD and BOD5 were reduced from 46,500 and 41,500 mg/L to 9000 and 6000 mg/L, respectively, within one month. The SO42− concentration, during the anaerobic period, was decreased from 1500 mg/L to 250 mg/L. The sequential treatment had positive effects on nitrification and denitrification efficiencies.

Changes in geotechnical properties of Municipal Solid Waste (MSW) in bioreactor landfill with degradation

Md. S. Hossain — 2011-07-20T23:20:50-05:00

Changes in geotechnical properties of Municipal Solid Waste (MSW) in bioreactor landfill with degradation
Md. S. Hossain, Kiran K. Penmethsa
International Journal of Environmental Engineering, Vol. 3, No. 3/4 (2011) pp. 349 - 370
The objectives of the research described in this paper are to: study the composition of fresh Municipal Solid Waste (MSW); study the effects of decomposition on physical characteristics of MSW in bioreactor landfill. Initially, composition of the fresh MSW constituents was determined based on 14 bag MSW samples. Then, four small-scale bioreactor landfills were simulated in laboratory and samples were prepared to represent each phase of decomposition. Laboratory tests were conducted to determine the changes in physical characteristics (moisture content, organic content, specific gravity, density and permeability) of MSW at each phase of decomposition and presented in this paper.

The impact of an environmental disamenity on land values: case of Kiteezi landfill in Uganda

Rosemary Emegu Isoto — 2011-07-20T23:20:50-05:00

The impact of an environmental disamenity on land values: case of Kiteezi landfill in Uganda
Rosemary Emegu Isoto, Bernard Bashaasha, Ateenyi Twaha Ali Basamba, John Mburu
International Journal of Environmental Engineering, Vol. 3, No. 3/4 (2011) pp. 371 - 387
The discourse on waste management is increasingly becoming important especially in developing countries. Landfill use is one of the most preferred methods of waste management yet it has various negative effects on people's welfare and livelihoods. This study uses hedonic price model to quantify impacts of proximity to a landfill. It uses primary data on property characteristics and other factors as explanatory variables. Land-price is used as a dependent variable. The results indicated that proximity to the landfill negatively affects land value whereas amenity variables positively influence land values. The study recommends appropriate policy on location and management of landfills.

Forum: Maintenance and rehabilitation of water resources and environment related infrastructures

Chin Y. Kuo — 2011-07-20T23:20:50-05:00

Forum: Maintenance and rehabilitation of water resources and environment related infrastructures
Chin Y. Kuo
International Journal of Environmental Engineering, Vol. 3, No. 3/4 (2011) pp. 388 - 390
How to maintain and rehabilitate a public facility has been a major responsibility of the agency in charge. Policies and procedures are normally documented in most of the agency's handbooks and manuals. It is not the intent of this forum to discuss those details for specific project or agency. Instead, some general thoughts and observations are shared here with the readers.

Forum: Communication skills: written and verbal

Chin Y. Kuo — 2011-07-20T23:20:50-05:00

Forum: Communication skills: written and verbal
Chin Y. Kuo
International Journal of Environmental Engineering, Vol. 3, No. 3/4 (2011) pp. 391 - 393
This Forum outlines some examples and opportunities of acquiring communication skills for scientists and engineers.

Coupling of a Probabilistic Cellular Automaton and a stochastic algorithm for a reactive transport simulation in subsurface media

Palanichamy Jegathambal — 2011-07-20T23:20:50-05:00

Coupling of a Probabilistic Cellular Automaton and a stochastic algorithm for a reactive transport simulation in subsurface media
Palanichamy Jegathambal, Holger Schuttrumpf, Jurgen Kongeter, Torsten Rose, Sankaralingam Mohan, Palani Sundarambal
International Journal of Environmental Engineering, Vol. 3, No. 3/4 (2011) pp. 394 - 409
The Operator Splitting scheme is a favourite and approved method for simulating multi component reactive transport systems. This scheme can easily be applied to the situation where large time scale differences between the transport and reaction steps exist. In the current work, different schemes of coupling such as Cellular Automaton and Gillespie Algorithm, and Finite Difference & Ordinary Differential Equation are studied. The verification and validation of the coupling schemes are done by applying these schemes to simulate one dimensional contaminant transport system with single decay, convergent reactions and double Monod kinetic reaction and comparing the results with analytical solutions.